Telephone calling device



March 18, 1958 E. L. KLINGEL 2,827,520

TELEPHONE CALLING DEVICE Filed Dec. 6, 1954 lNVENT OR EDWARD 1.. KLlNGEL ATTORNEYS- TELEPHONE CALLING DEVICE Edward L. Klingel, St. Paul, Minn.

Application December 6, 1954, Serial No. 473,2il2

7 Claims. (Cl. 179-90) The herein disclosed invention relates to telephone calling devices and has for an object to provide a device which will be simple and foolproof in construction and which can be manufactured at an economical cost.

Another object of the invention resides in providing a device in which gears and similar transmission elements have been eliminated to reduce the noise occasioned in the operation of the device.

The instant invention is particularly applicable to telephone calling devices utilizing supporting means in which a shaft is rotatably mounted and which carries a finger wheel movable past a fixed dial and opening and closing a switch successively as the shaft rotates.

An object of the invention resides in providing magnetic means between said shaft and supporting means and serving to retard the movement of the shaft sufiiciently to procure successive timed operation of the switch.

A still further object of the invention resides in utilizing a magnetic structure including a number of pole pieces carried either by the shaft or the supporting means and a core having a number of pole pieces carried by the other thereof and cooperating with said magnetic means and having mounted on the pole pieces thereof an electrical winding.

A still further object of the invention resides in constructing said magnetic structure with a permanent magnet having its poles at the ends of said magnet and in further applying to said magnet two pole facing members in the form of ferrous plates, each plate having pole pieces extending outwardly therefrom and lying in alternation to give to adjacent pole pieces opposite polarity.

Another object of the invention resides in constructing the magnet annular in form and in mounting the magnetic structure on said shaft with the magnet encircling the shaft.

Another object of the invention resides in constructing said winding from a strip of metal having a plurality of openings therein receiving the pole pieces of said core and carried thereby.

An object of the invention resides in constructing said plates in the form of discs with the pole pieces constructed as lugs bent outwardly therefrom and spaced from one another to receive the lugs of the other plate.

Another object of the invention resides in constructing the core with a number of pole pieces differing from the number of pole pieces of the magnetic structure.

Other objects of the invention reside in the novel combination and arrangement of parts and in the details of construction hereinafter illustrated and/ or described.

In the drawings:

Fig. l is a plan view of a telephone calling device illustrating an embodiment of the invention and looking at the obverse side thereof.

Pig. 2 is an elevational sectional view taken on line 2-2 of Fig. 1 and drawn to an enlarged scale.

Fig. 2 and drawn to the same scale as Fig. 1.

Fig. 4 is an inverted plan view of the calling device drawn to the same scale as Fig. 1 and looking at the reverse side thereof.

Fig. 5 is a perspective view of one of the pole facing members of the magnetic structure.

Fig. 6 is a perspective view of the permanent magnet of the invention.

Fig. 7 is a perspective view of the tensioning mechanism of the calling device.

Fig. 8 is a plan view of a portion of the winding of the invention.

The invention may be used with several types of calling devices, one of which has been illustrated and which includes supporting means providing bearings for rotatably supporting a shaft. Mounted on the supporting means and encircling the shaft is a dial and overlying said dial and secured to the shaft is a finger wheel having openings therein for the reception of the operators finger for rotating the same. The shaft carries a cam for operating a switch mounted on the supporting means and serving to successively open and close circuits of the telephone system to effect calling. The shaft is spring biased to return to normal position.

The invention proper incorporates a magnetic structure mounted on the shaft and including an annular permanent magnet encircling said shaft and having poles at the ends of the same. Overlying the poles of said magnet are two pole facing members which are constructed of ferrous sheet metal and are formed with plates in engagement with said poles and with ears struck outwardly from the peripheries thereof and disposed in the form of a cylinder. These ears are spaced from one another and the ears of one member intermesh with the ears of the other member to form pole pieces with the adjacent pole pieces having opposite polarity. Cooperating with the magnetic structure on the shaft is a core having inwardly extending pole pieces differing in number from the pole pieces on the magnetic structure. A winding consisting of a strip of metal is formed with holes receiving said pole pieces of the core. After the finger wheel has been rotated and released, the resilient means acting on the shaft causes reverse movement of the cam, thus operating the switch. During such movement, the magnetic structure and the core retard the velocity of said shaft suificiently to permit of opening and closing the switch at sutliciently spaced time intervals to properly actuate the calling mechanism of the telephone.

The telephone calling device shown in the drawings consists of supporting means 10 which includes a housing 11. This housing is constructed from sheet metal and is cupshaped in form having a bottom 12 and an annular wall structure 13 open at the upper end of the same. The housing 11 is closed by means of a closure 14 similarly constructed and which has a top 15 and a rim 15 depending therefrom. The rim 16 is snugly received within the annular wall structure 13 and is pressed into the same so that the top 15 closes the open end of the housing 11. Overlying the top 15 of closure 14 is a dial supporting annulus 17 which has mounted on it a dial 18. This dial is provided with numerals 19 printed thereon and which run from 1 to 0, said numerals being spaced apart, center to center, less than one-eleventh of the circumference of the dial. The annulus 17 is formed with a flange 21 which extends upwardly therefrom and which provides a central opening 22 in said annulus.

The housing 11 and the closure 14 are circular in form and the bottom 12 of the housing is provided with a bearing 23 secured thereto. In alignment with the bearing 23 .is another bearing 24 which is secured to the top 15 of closure 14. In this bearing is journaled a shaft 25 which has secured to the upper end of the same a finger Wheel 26. This finger wheel has a number of openings 'a shoulder 47 on said shaft.

and which limits the rotationahmovement imparted to the wheel 26 when the finger is inserted in one of the holes 27 and the finger-wheel rotated toward said stop. Movement of the shaft'25 in t he opposite direction is terminated by means of a stop 29 formed onthe flange 1 21 of annulus 17. A lug 31 extending downwardly from the finger wheel 26 is adapted to engage said lug when the wheel 26 occupies the position shown in Fig. l with the holes 27 in register with the numerals 19. 1

Mounted on the bottom 12 of housing ll is ,a block 32 1 whichhas secured to it a control switch 33 and acalling switch 34. The switch 34 has a fixed leaf 35and a movable leaf 36 insulated from one'another and from the block 32. ;An insulating finger 37 pivoted on a ointle 38 secured to the bottom 12 of housing 11 engages the movable lejaf 36 to open switch 34. 'This finger is constructed with a pin 39 adapted to be engaged by a numberof cams 41 arranged on a disc 42 mounted on shaft 25. There are as many cams 41 as: there are numerals 19 and the switch 34 can be caused to open and close' in accordance with-the operation of the finger wheel '26 thereby to effect operation of the calling device. overlying the disc 42 is another disc 43 which is provided with a cam 44 and which'operates the switch 33. The'two discs 42 and 43 are mounted upon a threaded section 45 of shaft 25 and on which is screwed a nut 46 urging the disc 42 against The intermediate portion 48 of shaft25is of greater diameter than the adjoining portions to form a shoulder 40, which, together'with the disc 42, engage the ends of the bearings 23 on opposite sides and restrain axial movement of the shaft in its bearings.

The shaft 25 is urged to rotate in a clockwise direction as viewed in Fig. 1 by means ofa torsion spring 49 which encircles the protruding end 51 of shaft 25. One end 52 of this spring is 'anchoredto the bottom 12 of housing 11 and the other end is attached to a slider 53 which is slidably and rotatably mounted on the protruding end 51 of shaft 25 and which has ears 54 extending outwardly inwardly and rotating the same, the tension on the spring 49 can be varied to'v ary the force produced by said spring in returning the shaft to normal position and in operating the'switches 33 and 34. Upon release of said slider, the cars 54 drop into the appropriate spaces 57 and effect a drive for shaft 25.

Disposed within the housing '11 and rotatably mounted on the intermediate portion 48 of shaft 25 is a magnetic structure indicated in its entirety by the reference numeral 58. This magnetic structure includes apermanent magnet 59 annular in form and which i smagnetized so that its poles are at the ends 61 and 62 of the same and so that the'flux travels in a direction parallel to the axes of shaft 25; This magnet encircles the portion 48 of shaft 25 and is mounted-between two pole facing members 63 and 64 shown in detail in Fig. 5. Both of these pole facing members being similar in construction, only the member 63 illustrated in said figure will bedescribed. This member is constructed from ferrous sheet'material to provide a plate 65 in the form of a disc and havinga central hole 66 forming a bearing rotatably mounted on the portion 48 of shaft 25. Extending longitudinally as pole pieces for the pole facing member. These pole pieces are spaced apart a distance-greater than the cirfrom the disc 65 area numberhof teeth '67 which serve cumferential extent of said poles to provide space 68 therebetween. The member 64 is arranged with respect to the member 63 so that its pole pieces are received within the spaces 68 and so that the pole pieces 67 of member 65 are received within the corresponding spaces of the member 64. All of the pole pieces 67 are situated radially the same distance from the axis of shaft 25 so that the pole pieces are arranged in cylindrical formation. By means of thisjconstruction, the pole pieces 67 on the member-63 all have the. same polarity, while the corresponding pole pieces on the member 64 have the same and the opposite'polarity. The two pole facing members 63 and and the magnet 59 are secured together by means of rivets 69 which pass through the discs 65 and which are received in notches 71 formed in the magnet 59.

The magnetic structure 58 is driven from shaft 48 by means'of a clutch 72. This clutch consistsof a torsion spring 73 which is wound about and frictionally engages the intermediate portion 48 of shaft 25. One end'74 of this spring is anchored to the pole facing member 64 as 25 travels freely relative to the magnetic structure 58.

When the said wheel is released, spring 49 urges shaft 25 'to rotate in the opposite direction. This causes the spring to become wrappedaround the portion 48 of shaft 25 and to drive the said shaft in a manner to cause the cams 41 and 44 to operate the switches 34 and 33.

Cooperating with the magnetic structure 59 is a core '75. This core is constructedwith a number of lamina- .tions 76 which are punched as best shown in Fig. 3.

These laminations are constructed with teeth 76 spaced from one another to form spaces 77 therebetween." These teeth form pole pieces for the core. The laminations are held together and attachedto the top 15 of the closure 14 by means of rivets 78 as shown in Fig. 2. Encircling the core '75 is a ring 79 of copper or other highly conducting material which is formed with a series of holes 81 in the same. This ring is mounted so that the teeth 76 are received in'the holes '81 and so that the bars 82' formed between said holes lie'in the spaces 77. The ring 79 may be split and the adjoining ends caused to abut one another when the ring is assembled or the ends secured together in any suitable manner. There is one less pole piece onthe core 75 than on the magnetic structure 59 which causes a uniform retarding action. One more pole piece may also beused.

. The operation of the invention is evident. When the shaft 25 is rotated in a clockwise direction, as viewed in Fig. 1, clutch 72. opens. and allows the .shaft to travel freely without urging rotation of the magnetic structure .58. As soon as the wheel 26 is released, spring 49 urges rotation in the opposite direction. The friction between the spring 73 and the portion 48 of shaft 25 now drives the magnetic structure/58.. The magnetic flux produced in the pole pieces 67 of the polejfacing members 63 and 64 passes through the core 75and due to the ring .79,

which forms a winding on said core, sets upa drag be- 7 tween the magnetic structure 58 and the core 75, which retards the reverse movement of shaft 25. This causes the shaft to rotate at a speed such'that the switch 34 may be operated in a manner to. effect proper operation of the calling device.

If desired, twice the number of pole pieces shown in the drawings may be used 'on the magnetic structure forming the rotor. In such case, the number of pole pieces on the stator would be two less or two more than the 'number of polepieces on the rotor instead of one less stator spanning the circumferential extent of the pole i pieces of one group'on" the rotor would be one less or one more in number. Such an arrangement has the advantage of providing amagnetic coupling for retarding the speed of rotation of the finger wheel whereby friction on the bearings for the shaft carrying the same is reduced.

The advantages of the invention are manifest. The number of moving parts in controlling the speed of the switch operating mechanism is reduced to a single rotating member. Reduction transmission such as gears or the like for operating a governor, is entirely done away with. The device is extremely quiet in operation. Due to a minimum of moving parts, friction is greatly reduced, and the device will continue to operate for a long period of time Without attention. A calling device embodying the features of the invention may be constructed at an extremely economical cost.

Changes in the specific form of the invention, as herein described, may be made within the scope of what is claimed without departing from the spirit of the invention.

Having described the invention, what is claimed as new and desired to be protected by Letters Patent is:

1. In a telephone calling device, supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, said shaft and supporting means having corresponding parts, a magnetic structure including a number of pole pieces and carried by one of said parts, a core having a number of pole pieces differing in number from the number of said first named pole pieces by two and carried by the other part, the pole pieces on said shaft being movable past the pole pieces on said supporting means and windings on the pole pieces of said core and functioning to retard the movement of said shaft brought about by said resilient means.

2. In a telephone calling device, supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the Wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, said shaft and supporting means having corresponding parts, a magnetic structure including a number of pole pieces and carried by one of said parts, a core having a number of pole pieces differing in number from the number of said first named pole pieces by one and carried by the other part, the pole pieces on said shaft being movable past the pole pieces on said supporting means and windings on the pole pieces of said core and functioning to retard the movement of said shaft brought about by said resilient means.

3. In a telephone calling device, a supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, a rotor mounted on said shaft and comprising two spaced ferrous circular plates secured to said shaft, an annular permanent magnet encircling said shaft and having its poles at the ends thereof and contacting said plates, pole pieces extending outwardly from each of said plates and toward the opposite plate, the pole pieces on one plate alternating with the pole pieces of the other plate and lying in a common cylindrical zone, said magnet causing the adjacent pole pieces to have opposite polarity, a core carried by said supporting means and having a difierent number of pole pieces disposed in juxtaposition with reference to the pole pieces on said rotor, and a winding on said core causing a drag on said rotor as the same rotates relative to said core.

4. In a telephone calling device, supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger Wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, a rotor mounted on said shaft and comprising two spaced ferrous plates driven by said shaft, an annular permanent magnet encircling said shaft and having its poles at the ends thereof and engaging said plates, pole pieces extending outwardly from said plates and arranged in circular formation adjacent one another, a core carried by said supporting means and having a number of pole pieces disposed in juxtaposition with reference to the pole pieces on said rotor and a winding on said core causing a drag on said rotor as the same rotates relative to said core.

5. In a telephone calling device, supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, a rotor mounted on said shaft and comprising two spaced ferrous circular plates secured to said shaft, an annular permanent magnet encircling said shaft and having its poles at the ends thereof and engaging said plates, axial pole pieces on said plates extending toward the opposite plate, the pole pieces on one plate alternating with the pole pieces of the other plate and lying in a common cylindrical zone, said magnet causing the adjacent pole pieces to have opposite polarity, a core carried by said supporting means, a different number of radial pole pieces on said core disposed in juxtaposition with reference to the pole pieces on said rotor, and a winding having openings therein extending along the same, said winding being applied to the core with the pole pieces thereof extending through said openings, said winding causing a drag on said rotor as the same rotates relative to said core.

6. in a telephone calling device, supporting means, a shaft carried thereby and rotatable relative thereto, a dial mounted on said supporting means, a finger wheel attached to said shaft and serving to rotate the same, resilient means acting between said supporting means and shaft and stressed upon manual rotation of the wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated by said shaft upon movement in the last named direction, said shaft and supporting means having corresponding parts, a magnetic structure including a number of groups of even numbered pole pieces carried by one of said parts, a core carried by the other of said parts and having the same number of group of pole pieces as the magnetic structure, the number of pole pieces in each group of the core difiering from the number of pole pieces in each group of the magnetic structure by one, the pole pieces on said shaft being movable past the pole pieces on said supporting means and windings on the pole pieces of said core and functioning to retard the movement of said shaft brought about by said resilient means.

7. In a telephone calling device, supporting means, a shaft carried therebyand rotatable relative thereto, a dial mounted on said supporting means, a finger wheel at- 'tached to said shaft and sewing toro tat e the same, resilient means acting between saidsupporting means and shaft and stressed upon manual rotation of the" wheel in one direction to urge rotation of the shaft in the opposite direction, switch means operated: by said shaft upon movement in the-1ast-named direction, amagnetic structure carried by said shaft and-inc1udinga number of groups of even numbered pole pieces, 'a core carried 'by said supporting means and having the same number of groups of pole pieces as the magnetic s'tructure,the number of pole pieces in each group of the core differing from the number of pole pieces in each group of the magnetic structure by one, the pole pieces on said shaft being movable past the pole pieces on said supporting means and windings on the pole pieces of said core and functioning to retard the movement of said shaft brought 6 about by said resilient means.

References Cited in the file of this patent UNITED STATES PATENTS 

